Many kitchens and pantries in the area are currently dealing with CFFI and AFFI: Chronic and Acute Fruit Fly Infestation.
Chronic Fruit Fly Infestation or CFFI, leaves you with enough visibility to see across the table to your spouse. In the acute condition it can be hard to find the refrigerator- from the kitchen sink. Fortunately there are easy, non toxic ways to get rid of the pests. If you don't mind killing the flies, mix vinegar and/or red wine with an equal amount of water. Add a little sugar, and a few drops of dish soap. Put a few small dishes out near the fruit bowl, and the refrigerator - if you can find it. The drosophila, or vinegar flies will soon litter the bottom of the bowl.
You can construct a catch and release trap by making a cone of paper with a pencil diameter small end. Place it in a clear jar so that the cone sits a few inches from the bottom. Ripe fruit, vinegar, or wine in the bottom of the jar will attract the flies. You can take the trap outside and release them if you like. Just close the door while you do this so they don't fly right back into the kitchen. Finally, if you open the compost, or find the tomato that has turned into a fruit fly condominium, you may need to deal with an Acute Infestation. A hand held cordless vacuum can make quick work of the black cloud. Hey- we're lucky to have this problem. It's a symptom of all the fresh fruit Oregon produces each summer. And we will be lucky until November- when the fruit supply tapers off.